On this date in 1821, the Plan of Iguala proclaimed Mexico's independence from Spain. Tucson passed from Spanish to Mexican rule. This image shows a watercolor by Russell Bartlett called "Tucson, Sonora from the S.W. July 18, 1852."

The old corral at the CO Bar ranch on Hart Prairie, San Francisco Mountain from the inside. [Forrest:] The ruins of the old log bunkhouse are seen just to the left and a more recent bunkhouse and cookhouse to the right.